Finding the Fourth Proportional to 105.83, 145.89 and 80.94

Step by Step Solution

1. Step 1: Write the proportion equation
   105.83 : 145.89 = 80.94 : x
2. Step 2: Convert to fraction form
   105.83/145.89 = 80.94/x
3. Step 3: Cross multiply
   105.83x = 145.89 × 80.94
4. Step 4: Simplify right side
   105.83x = 11,808.88
5. Step 5: Solve for x
   x = 11,808.88/105.83
6. Step 6: Final answer
   x = 111.58